Hey! Welcome to transitioning. I've only been transitioning for 5 months, but I'll try to tell you what I know:

Cowashing is washing your hair with conditioner only. You can do this because shampoos often contain alot of ingredients that aren't good for natural hair. So you wash your hair with conditioner instead of shampoo and you can do this as much as you like. Cowashing helps to keep my hair moisturized and soft. I cowash once or twice a week with Suave Tropical Coconut conditioner. Alot of people use the more inexpensive conditioners for cowashes because you use ALOT of it and you can follow it up with another conditioner. I follow up with the Organix Coconut conditioner. I got both of these from Target,

Deep Conditioning is another way to restore moisture to your hair. Most of the advice I have seen suggests that you deep condition your hair at least once a week. There are many websites that can show you how to make your own deep conditioner, but I just use Organic Root Stimulator Deep Conditioning pack. I also bought it from Target (I love Target). You apply deep conditioner after your wash or cowash and you normally put on a plastic cap and let it sit in your hair for a little while. It just helps replenish your hair and helps to keep it moisturized.

I don't know much about hot oil treatments. I know that they can help with frizziness and help to moisturize your scalp. I do have an oil product that I use on my scalp. It is a mixture of different oils and I found it at Sally's. It keeps my scalp from being dry and I also read that it is suposed to help with hair growth, but I'm not sure how true that is.

I know I probably left something out or said something wrong, but this is a great website and I'm pretty sure that the rest of the lovely ladies on this forum will have more things to add. I hope some of this helps! Happy transitioning!!!